Adaptive polarimetric image representation for contrast optimization of a polarized beacon through fog

We present a contrast-maximizing optimal linear representation of polarimetric images obtained from a snapshot polarimetric camera for enhanced vision of a polarized light source in obscured weather conditions (fog, haze, cloud) over long distances (above 1 km). We quantitatively compare the gain in contrast obtained by different linear representations of the experimental polarimetric images taken during rapidly varying foggy conditions. It is shown that the adaptive image representation that depends on the correlation in background noise fluctuations in the two polarimetric images provides an optimal contrast enhancement over all weather conditions as opposed to a simple difference image which underperforms during low visibility conditions. Finally, we derive the analytic expression of the gain in contrast obtained with this optimal representation and show that the experimental results are in agreement with the assumed correlated Gaussian noise model

Differential description and irreversibility of depolarizing light-matter interactions

The widely-used Jones and Mueller differential polarization calculi allow non-depolarizing deterministic polarization interactions, known to be elements of the $SO^+(1,3)$ Lorentz group, to be described in an efficient way. In this Letter, a stochastic differential Jones formalism is shown to provide a clear physical insight on light depolarization, which arises from the interaction of polarized light with a random medium showing fluctuating anisotropic properties. Based on this formalism, several "intrinsic" depolarization metrics naturally arise to efficiently characterize light depolarization in a medium, and an irreversibility property of depolarizing transformations is finally established

Multi-agent planning and scheduling, execution monitoring and incremental rescheduling: Application to motorway traffic

This article describes a planning method applicable to agents with great perception and decision-making capabilities and the ability to communicate with other agents. Each agent has a task to fulfill allowing for the actions of other agents in its vicinity. Certain simultaneous actions may cause conflicts because they require the same resource. The agent plans each of its actions and simultaneously transmits these to its neighbors. In a similar way, it receives plans from the other agents and must take account of these plans. The planning method allows us to build a distributed scheduling system. Here, these agents are robot vehicles on a highway communicating by radio. In this environment, conflicts between agents concern the allocation of space in time and are connected with the inertia of the vehicles. Each vehicle made a temporal, spatial, and situated reasoning in order to drive without collision. The flexibility and reactivity of the method presented here allows the agent to generate its plan based on assumptions concerning the other agents and then check these assumptions progressively as plans are received from the other agents. A multi-agent execution monitoring of these plans can be done, using data generated during planning and the multi-agent decision-making algorithm described here. A selective backtrack allows us to perform incremental rescheduling

Depolarization remote sensing by orthogonality breaking

A new concept devoted to sensing the depolarization strength of materials from a single measurement is proposed and successfully validated on a variety of samples. It relies on the measurement of the orthogonality breaking between two orthogonal states of polarization after interaction with the material to be characterized. The two fields orthogonality being preserved after propagation in birefringent media, this concept is shown to be perfectly suited to depolarization remote sensing through fibers, opening the way to real time depolarization endoscopy.Comment: 5 pages, 4 figure

Theoretical optimal modulation frequencies for scattering parameter estimation and ballistic photon filtering in diffusive media

The efficiency of using intensity modulated light for estimation of scattering properties of a turbid medium and for ballistic photon discrimination is theoretically quantified in this article. Using the diffusion model for modulated photon transport and considering a noisy quadrature demodulation scheme, the minimum-variance bounds on estimation of parameters of interest are analytically derived and analyzed. The existence of a variance-minimizing optimal modulation frequency is shown and its evolution with the properties of the intervening medium is derived and studied. Furthermore, a metric is defined to quantify the efficiency of ballistic photon filtering which may be sought when imaging through turbid media. The analytical derivation of this metric shows that the minimum modulation frequency required to attain significant ballistic discrimination depends only on the reduced scattering coefficient of the medium in a linear fashion for a highly scattering medium

\u3cem\u3eVitis\u3c/em\u3e Seeds (Vitaceae) from the Late Neogene Gray Fossil Site, Northeastern Tennessee, USA.

This study focuses on the morphometric and systematic studies of fossil vitaceous seeds recently recovered from the Gray Fossil Site (7-4.5 Ma, latest Miocene-earliest Pliocene) northeastern Tennessee. Morphologically, all fossil seeds correspond to the extant subgenus Vitis (genus Vitis) of the Vitaceae based on the smooth dorsal surface with a centrally positioned chalaza connected with a conspicuous chalaza-apex groove and short linear ventral infolds that are slightly diverged apically. A multivariate analysis based on 11 measured characters from 76 complete seeds identified three types of seeds, each representing a distinct morphotaxon. Based on comparison with modern and fossil vitaceous specimens, three new species were recognized: Vitis grayana sp. nov., Vitis lanatoides sp. nov., and Vitis latisulcata sp.nov. The close resemblance between the first two fossil grapes (Vitis grayana and Vitis lanatoides) with extant eastern Asian Vitis provides further evidence that the eastern Asian floristic elements existing in the southeastern North American flora continued to as late as late Neogene

Healthcare vs. Hawkishness: The Divergent Effects of Affect on Context-Driven Shifts in Attitudes

There is a tradition of research in affective science suggesting different affective states (e.g., anger vs. anxiety) are associated with relatively unique goals and motives (Frijda, 1986; 1988; Schwarz & Clore, 2007, Lerner & Keltner, 2000; 2001). Although this approach has received considerable empirical support, this work has yet to fully resolve an important issue. For any given type of emotion (say, anger), such feelings can be activated in a variety of different triggering contexts. If so, to what extent does the triggering context matter when examining the consequences of that emotion for attitudes? Some findings suggest that context does not matter (Johnson & Tversky, 1983), whereas others imply that context should matter (Frijda, 1988; Smith & Ellsworth, 1985). In my dissertation, I examine the role of context as it bears on the relationship between affect and judgment, across different threatening contexts (terrorism, healthcare). Across 3 Experiments, I find the role of affect, and its effects on attitudes, are contingent on the context in which the affect is activated. These findings demonstrate that the role of context plays an important role in understanding when, if, and in which direction, affect plays a role in shaping attitudes and behavior

Towards a Greater Understanding of the Antecedents of Dehumanization: A Contempt-Dehumanization Framework

Although dehumanization has been studied in a variety of conceptual and methodological paradigms, surprisingly little is known about the role of affect as a mediator of the dehumanization process. In this paper we propose and test a contempt-dehumanization model, which stipulates that, the effect of severe norm violations on dehumanization is indirect, as mediated by contempt: norm violation ! contempt ! dehumanization). Across three studies we provide consistent support for this model in the realm of extremely immoral acts committed by drug dealers who intentionally target young children: Experiments 1 and 3) as well as unscrupulous Wall Street businessmen who deliberately scam unsuspecting elderly investors: Experiment 2). We discuss the implications of our model for previous models of dehumanization

An Ecological Study on A Sand County Almanac

Aldo Leopold is an American author, scientist, ecologist, conservationist, environmentalist, whose most outstanding and representative work A Sand County Almanac is filled with abundant and deep ecological thoughts. This paper intends to explore Leopold’s ecological thoughts in this book. First, Leopold redefines the relationship between nature and human beings. He states that human beings are part of nature and should show love and respect for it; second, Leopold proposes the famous and significant land ethic theory, which establishes a basis for new ecological ethics. He enlarges the ethic range to land and to the whole nature, sets the criteria of land ethic, and describes the importance of ecological conscience which is fundamentally helpful to solve ecological crisis and protect the ecosystem; third, Leopold elaborates on the values of wilderness, such as the recreational value,the ecological value, the aesthetic value, the scientific value, the ecological value and the cultural value.Nowadays, all these ecological thoughts are still meaningful for people to know and love the nature, to protect the land and the wilderness

General Cram\'er-Rao bound for parameter estimation using Gaussian multimode quantum resources

Multimode Gaussian quantum light, including multimode squeezed and/or multipartite quadrature entangled light, is a very general and powerful quantum resource with promising applications to quantum information processing and metrology involving continuous variables. In this paper, we determine the ultimate sensitivity in the estimation of any parameter when the information about this parameter is encoded in such Gaussian light, irrespective of the exact information extraction protocol used in the estimation. We then show that, for a given set of available quantum resources, the most economical way to maximize the sensitivity is to put the most squeezed state available in a well-defined light mode. This implies that it is not possible to take advantage of the existence of squeezed fluctuations in other modes, nor of quantum correlations and entanglement between different modes. We show that an appropriate homodyne detection scheme allows us to reach this Cramr-Rao bound. We apply finally these considerations to the problem of optimal phase estimation using interferometric techniques